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Concentrations of Ca, Cd, Cu, Fe, and Pb and binding capacities for Cd, Cu, and Pb were determined for water samples collected
from 12 lakes in southwestern Maine using atomic absorption and ion-selective electrodes, respectively. Surface waters in
this area are soft and characterized by low pH. Some lakes were highly colored with refractory organics, whereas others had
very low organic carbon concentrations. Both Cu and Pb concentrations were positively correlated with organic carbon content.
Copper and Pb binding capacities were significantly correlated with organic carbon content, whereas Cd binding capacity was
positively correlated with pH, but not with organic carbon. Surface water binding capacity for Pb was greater than that for
Cu or Cd. More than 99% of the Ca from all waters studied was removed onto cationic exchange resins. Less than 1% of the total
Cu existed as cationic species in highly humic waters, whereas as much as 65% existed as cationic species in less huic waters.
Conversely, more than 99% of the Cd present in humic waters existed as cationic species, whereas as little as 50% existed
as cationic species in less humic, more alkaline waters. These correlative studies indicate that binding by organic carbon
is important for both Cu and Pb in this area and must be considered in models of trace metal speciation. However, Cd binding
in the same waters is not correlated with organic carbon, which does not need to be considered in speciation models for Cd. 相似文献
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The NW corner of the Little Hungarian Plain, which lies at the junction of the Eastern Alps, the Pannonian Basin and the Western Carpathians, is a neotectonically active region linking the extrusional tectonics of the Eastern Alps with the partly subsiding Little Hungarian Plain. The on-going deformation is verified by the earthquake activity in the region. An extremely flat part of the area, east of Neusiedlersee, the so-called Seewinkel, has been investigated with Airborne Laser Scanning (ALS, also known as airborne LiDAR) techniques, resulting in a digital terrain model (DTM) with a 1 m grid resolution and vertical precision of better than 10 cm. The DTM has been compared with known and inferred neotectonic features.Potential neotectonic structures of the DTM have been evaluated, together with geological maps, regional tectono-geomorphic studies, geophysical data, earthquake foci, as well as geomorphological features and the Quaternary sediment thickness values of the Seewinkel and the adjacent Parndorfer plateau. A combined evaluation of these data allows several tectonic features with a relief of < 2 m to be recognized in the DTM. The length of these linear geomorphological structures ranges from several hundred meters up to several kilometers. The most prominent feature forms a 15 km long, linear, 2 m high NE–SW trending ridge with gravel occurrences having an average grain size of ca. 5 cm on its top. We conclude this feature to represent the surface expression of the previously recognized Mönchhof Fault. In general, this multi-disciplinary case study shows that ALS DTMs are extremely important for tectono-geomorphic investigations, as they can detect and accurately locate neotectonic structures, especially in low-relief areas. 相似文献
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Total concentrations of and binding capacities for Cd, Cu, and Pb were measured in selected surface waters from northwestern Europe. Linear multiple regression predictive models explained 97, 93, and 96% of the observed variation in Cd, Cu and Pb binding capacities, respectively. The models constructed used (CO23?) and (SO22?) to predict Cd binding capacity, (OH?) and (SO42?) to predict Cu binding capacity and (OH?), (CO32?) and (SO42?) to predict Pb binding capacity. Organic carbon was not significantly correlated with binding capacities for Cd, Cu, and Pb and was unimportant in explaining a significant amount of the variability in binding capacities for the metals of northern European surface waters. Thus, the effects of these organics on trace metal speciation can be ignored and predictive models of trace metal speciation constructed, using inorganic solubility equilibria only. Ratios of total Cd, Cu, and Pb concentrations to their respective binding capacities were much less than unity for all waters studied. Copper exhibited the greatest metal concentrations: binding capacity ratio in all waters investigated. 相似文献
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Local accuracy measures for digital terrain models 总被引：1，自引：0，他引：1
Karl Kraus Wilfried Karel Christian Briese Gottfried Mandlburger 《The Photogrammetric Record》2006,21(116):342-354
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